Finishing up

Fit, fasten, and fair off the small chunk of dead wood at the forward end of the casting. Then fair off the sides of the wood keel, between the rabbet and the top of the casting. Use a quick-turn adze here, and expect to re-grind it every time you hit the iron. Finish with round-sole

plane and disc sander. Clean the iron with the disc grinder and a wire brush, and build up a surface with whatever anti-rust and barrier coats you believe in. We have tried everything from red lead to super-epoxy and would hate to guarantee any one of them. I would probably use two coats of ZRC, which stands for zinc-rich coating, and insulate it with some kind of inoffensive barrier paint before the final anti-fouling goes on. Ask your experts what to use.

Appendix B

A ballast keel filled out with deadwood

Suppose your design calls for a ballast keel scarfed at its after end that must be faired out with deadwood to the sternpost. This is the usual construction, for good and sufficient reasons which I will ignore right now. The problem is, of what do you make this deadwood, how do you fit it, and how do you fasten it?

Let's go through the various moves to be made. Suppose we build this deadwood right-side up, working from the top down. This plan poses two small problems: first, what to hang it to above, and second, how to get under it in order to bore up through the scarfed end by way of the cored holes in the casting. The latter problem can be solved by setting the casting high up on blocking, or by supporting it over a narrow trench. For the first, the obvious answer is, of course, to hang the deadwood from the boat's actual (wood) keel, whether at this point it is bare or already fitted with stem and sternpost.

Let me assume that the ballast keel casting is now upright, adequately supported on strategically placed crosstimbers to allow access from below to all bolt holes, braced to keep the flat top precisely level athwartships, and approximately level fore-and-aft. (See Figure B-l). This care is necessary so that you can determine the true centerline of the casting, from its forward end to the aftermost end of the figure B-1

Casting carefully leveled athwartships

Center of casting at forward end

Leveled more or less fore-and-aft

Center of casting at after end

Centerline of casting's top surface obtained with straightedge scarf, which is, of course, below the plane of the flat top. Do this with a straightedge, centered at the forward end of the casting, and located by a plumb bob over the aft end. The point at which this line leaves the after end of the flat is not necessarily the mathematical center at that point (because of possible irregularities in the top of the casting), but it is the one that must coincide with the true centerline on the underside of the wood keel.

Place the keel carefully in position on the casting now, and bore up through it, in the way of the flat, at least two holes for keel bolts. It would be advisable to use temporary bolts at this stage, a bit undersized so as to be easily removable. The overhanging after end of the keel will tend to sag downward of its own weight. Lay a timber across its top and block up the ends, and thus keep everything wide-open underneath. You now have a large vacancy, about as shown in Figure B-2, to be filled with a block of deadwood that tapers in profile, in plan view, and from top to bottom. This must be fitted worm-tight, if not watertight, to the end of the ballast casting, and it must be strong enough to withstand severe abuse in the event of a grounding. And if you can work it so that the bottom surface is sacrificial (like the after end of that mythical snake that steamed away with pilothouse and engine room intact, leaving only gristle between the pursuing jaws), so much the better. Your designer very wisely draws an outline, labels it "oak/' and leaves you to your own devices.

Let's make it of timber with high moisture content, so that it won't swell and overhang the metal casting, nor yet build up an intolerable load on the bolts that tie it to the keel. Let's make it in layers, each of which can be cut to shape (in plan view) with the saw that you used on the keel. Finally, let's finish off at the bot-

torn with an especially hard piece, 3 inches thick, spiked or screw-fastened to the main body of the deadwood, and independent of the main fastenings, rudderpost, and gudgeons— in short, a shoe piece that is easily replaceable if it gets chewed-up, worm-eaten, or otherwise obnoxious.

We'll use oak flitches, sawn clear of the heart, 4, 5, or 6 inches thick as necessary to build the pile and come out even. A friendly and patient sawyer can taper one of these in profile to your pattern with the big board saw; otherwise, you'll have to do it with your small

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How To Have A Perfect Boating Experience

How To Have A Perfect Boating Experience

Lets start by identifying what exactly certain boats are. Sometimes the terminology can get lost on beginners, so well look at some of the most common boats and what theyre called. These boats are exactly what the name implies. They are meant to be used for fishing. Most fishing boats are powered by outboard motors, and many also have a trolling motor mounted on the bow. Bass boats can be made of aluminium or fibreglass.

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